October 1, 2002
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story tips, please contact the public information
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Editor: Josh Chamot
Contents of this News Tip:
Soot Contributes
to Droughts and Floods in China
A new climate study has found that soot particles composed
of black carbon and other pollutants are causing precipitation
and temperature changes in China and may be partially
responsible for the increased floods and droughts
in the region over the past several decades.
In research funded by the National Science Foundation
(NSF) and NASA, Surabi Menon of both NASA and Columbia
University in New York, and her colleague, James Hansen
of NASA's Goddard Institute for Space Studies in New
York, have found that black carbon can affect regional
climate by absorbing sunlight, which heats the air
and thereby alters large-scale atmospheric circulation
and the hydrologic cycle. The research appears in
the September 27 Science.
In recent years, northern China has suffered from increasingly
severe dust storms, while increased rainfall in southern
China is perhaps the largest change in precipitation
since the year 950. Using a climate computer model
and aerosol data from 46 ground stations in China,
Menon and Hansen conducted four sets of computer simulations
to monitor the effects of black carbon over China
and India.
From the simulations, the researchers found that increased
amounts of soot over southern China could lead to
the same pattern of southern flooding and northern
droughts that has existed over the past several years.
"If our interpretation is correct, then reducing the
amount of black carbon or soot may help diminish the
intensity of floods in the south and droughts in the
northern areas of China, in addition to having human
health benefits," Hansen said. Currently, the researchers
are also studying a similar pattern over India.
Black carbon or soot is generated from industrial pollution,
traffic, outdoor fires and household burning of coal
and biomass fuels. Emissions are large in China and
India because cooking and heating are done with wood,
field residue, cow dung, and coal, at a low temperature
that does not allow for complete combustion.
When soot absorbs sunlight it heats the air and reduces
the amount of sunlight reaching the ground. The heated
air rises and makes the atmosphere more unstable,
bringing rainfall to regions that are heavily polluted.
[Cheryl Dybas]
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Earthquake
Study Produces New Depiction of Fault Zones
On October 16, 1999, approximately 37 miles from Palm
Springs, California, a magnitude 7.1 earthquake ripped
through 28 miles of faults in the Mojave Desert. Because
of the area's sparse population and development, the
massive quake caused no major injuries or destruction.
Yet, the "Hector Mine" event, named after a long-abandoned
mine in the area, has produced a trove of information
about earthquakes, faults, and ruptures for NSF-funded
scientists at the Scripps Institution of Oceanography
at the University of California at San Diego. These
scientists, along with a colleague at the California
Institute of Technology (Caltech), used satellite
and radar data to uncover previously undocumented
fault properties.
The new findings include the first evidence that faults
move backwards and indications that the material within
faults is significantly different from surrounding
material.
Yuri Fialko of the Scripps Institution, the lead scientist
on the study, says the results may lead to new ways
of identifying potentially active faults, tracking
when the last earthquake occurred in a fault zone,
and better understanding the earthquake process.
"Even small stress perturbations from distant earthquakes
can cause faults to move a little bit, but it's only
been known to cause this motion in a forward sense,"
said Fialko. "Here we observed the faults coming backwards
due to relatively small stress changes, which is really
quite unusual." The backward motion on the faults
is caused by the different materials within the faults,
rather than a frictional failure.
According to Fialko, the results will guide new seismic
studies to areas with contrasting fault material,
and can then be used as a way of identifying potentially
active faults. [Cheryl Dybas]
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Earthquake
Testing Equipment Will Be Connected to National Network
Five new NSF awards will provide advanced research
and experimental equipment that will evaluate the
impact of earthquakes. Researchers from across the
United States are studying the effects of earthquakes
in relation to building design, advanced materials
and other measures that can minimize earthquake damage
and loss of life.
The awards are part of NSF's George E. Brown, Jr. Network
for Earthquake Engineering Simulation (NEES). The
high-speed Internet network, when completed in 2004,
will remotely link researchers with tools for testing
and improving the seismic design and performance of
structures, utilities and other infrastructure. NSF
will invest a total of about $82 million under NEES
for new and upgraded equipment and the computer network
that will connect the equipment facilities.
Integration of the equipment is being managed by the
University of Illinois at Urbana-Champaign. The equipment
and network system will be managed by a consortium
to be selected at a later time.
The five new awards, totaling $15.5 million over two
years, will fund construction, expansion and modernization
of equipment at five U.S. universities, Cornell, Brigham
Young, and Lehigh Universities and the Universities
of California (San Diego) and Illinois (Urbana-Champaign).
These awards complement the 11 equipment grants announced
in early 2001 and provide new earthquake engineering
testing capabilities for large-scale structural response
and soil-foundation-structure interaction. [Amber
Jones]
For more information, see:
http://www.eng.nsf.gov/nees
and
http://www.nsf.gov/od/lpa/news/press/01/pr0110.htm
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Geometry Software
Eases Math Education, Visualization
In a recent survey conducted by the Center for Research
on Information Technology and Organizations, math
teachers rated The Geometer's Sketchpad as
the most valuable software for students.
The Geometer's Sketchpad, developed with support
from NSF, provides colorful, graphic learning tools
that make mathematics easier to teach and learn. The
software is designed for an audience ranging from
middle school students to research mathematicians
and allows users to "draw" geometric figures and mathematical
diagrams using virtual versions of the compass, the
straightedge, and other standard mathematical tools.
The visualization software and student guides were
developed by Key Curriculum Press and its research
affiliate KCP Technologies, Inc., of Emeryville, California,
with funding from NSF's Small Business Innovation
Research program.
The latest version, Sketchpad 4.0, is the
result of more than four years of research, development
and field-testing in schools and universities across
the country, and it incorporates powerful new tools
for algebra, trigonometry and calculus. Version 4.03,
released in August 2002, adds Macintosh OS X to the
list of operating systems the software supports. [Amber
Jones]
For more information, see:
http://www.keypress.com/sketchpad
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